Latest Issue

The rise of the recycling robots

No longer the stuff of science fiction or Pixar films, robots are starting to make inroads into the world of recycling. Will Simpson meets the machines of the future

Photo: ZenRobotics

It looks like it’s finally here. Barely a week goes by now without a news report alerting us to developments in artificial intelligence, together with exciting (or scary) predictions about what this means for us as humans. After years lurking on the fringes of our imagination (or at least confined to science fiction), it seems as if the era of mass robotisation may actually be upon us. And like every other sector – and, indeed, sphere of human existence – waste and recycling could be profoundly affected.

There is, of course, already a degree of automation within the industry, especially at material recovery facilities (MRFs). What are near-infrared (NIR) sensors, but automated machines that already reduce the need for humans to laboriously sift through dirty materials?

In parts of the waste industry, there are already a number of unusual and interesting robotic applications we could see more of in the coming years. We reported last year on the unmanned aerial vehicles (read: drones or even ‘flying robots’) that are being used to monitor some landfill sites, as well as record (and reduce) crop and construction waste (see Resource 81). And then there is the example of ‘Liam’, the 29-armed Californiabased Apple robot that can dissemble iPhones at a phenomenal rate – one every 11 seconds. Apple has plans for a Europe-based version of Liam that will be adapted so it (he?) can also handle other iOS models, including iPads and iPods.

Closer to home, there is the example of North Bristol NHS Trust, which has introduced AGVs (automated guided vehicles) into the newly-redeveloped Southmead Hospital (see Resource 79). The collaboration between the bin manufacturer Taylor and automative specialists Swisslog (which has been producing similar systems for hospitals on the Continent for some time now) sees 800-litre containers sitting atop Swisslog’s TransCar® AGVs to transport waste, linen, food, consumables, certain pharmaceuticals and instrumentation around the hospital, with the aim of freeing up portering time to deliver patient-facing services. The AGVs can be called to collect different waste streams from holding bays, using laser navigation to identify any obstacles that might hinder progress, and opening and closing doors and summoning lifts by communicating with the hospital central system via a wireless network.

Photo: ZenRobotics

There is also the so-called ‘dustbot’, another AGV system, which has been developed by the Scuola Superiore Sant’Anna CRIM laboratory in Pisa, Italy. This little fellow is designed to collect waste from domestic households. Using Segway technology and a GPS system, it can navigate around the city, stopping at preprogrammed destinations, where users can drop off their rubbish into the dustbot’s belly before it is taken back to a central location.

These, though, currently exist as novelties, their widespread usage unlikely to spread any time soon. Perhaps more significant in the longer term will be the use of robotics in sorting and processing waste, which has already started to make gradual inroads. Indeed, this had already started at the turn of the decade, when Dutch firm Bollegraaf attempted to develop a robotic sorting system to handle mixed municipal waste. However, the company’s trials did not appear to go to plan, with commentators saying that the mixed municipal stream was too complicated – and nothing more was heard about the Bollegraaf robot. The firm did not respond to a request for an interview about the trial.

More successful, though, have been two tech firms from opposite ends of Europe, which are using robots to sort more uniform waste streams. ZenRobotics is a Finnish company that has put together a system based on what it calls ‘machine learning’. In effect, this means that, unlike assembly line robots that merely repeat the same action, ZenRobotics’s robots ‘learn’ from information that is fed to them via NIR spectroscopic cameras, 3D laser scanners and metal sensors that lie along the conveyor belt. “That means that the robots are able to make autonomous decisions on what to sort out”, explains Janica Johansson, ZenRobotics’s Marketing Director. “There is no human involvement in the sorting process, and the robots are not pre-programmed to do anything. One of the benefits of our software [is] that it actually can adapt to the changing waste streams.”

ZenRobotics started its robots off sorting construction and demolition waste, but over time has slowly introduced them to other waste streams, such as industrial waste. The machines can differentiate between metals of different shapes and colours, but not yet different alloys. And more challenging yet are sorting puzzles such as plastic polymers, which would certainly leave them flummoxed. At least, at present.

Currently, ZenRobotics Recycler (ZRR) systems are in operation in plants in Holland, Switzerland and Finland, with others due to open later in the year in France and Japan. “There is a huge interest in these robotic applications”, says Johansson. “Interest has been growing rapidly over the last six months or so.”

Meanwhile, in Spain, recycling robots are being investigated by Sadako Technologies, a Barcelona-based firm that has christened its creation Wall-B. “Just like in the Pixar film,” laughs Belen Garnica the Co-Founder of Garnica, “except it’s a previous version.”

Wall-B, described by the company as ‘a high-speed industrial robotic arm with a grasping by suction system plus a state of the art computer vision system’ that can overhang conveyor belts, is already used at two processing plants near Barcelona. The developers expect that it will be able to take over the work of manual human sorters in identifying valuable materials from a mixed flow, rather than replacing existent NIR systems used at most MRFs. “We are not trying to compete with nearinfrared systems”, explains Garnica. “They can process a lot of material very quickly and efficiently. But when you have some streams that you don’t have enough valuable material to install [an NIR] machine or maybe after the [NIR] machine you need to put a person separating, that’s where Wall-B will be useful.

“It’s flexible, it can recover more than one material at the same time and can also be adapted to the plant’s needs very quickly – if you want to change the materials you want it to recognise you just make software changes, not any hardware changes.”

Sadako Technologies' Wall-B machine

Photo: Sadako Technologies

That’s one advantage of robotic systems. There’s also the fact that they are quick – Wall-B can do 20 picks per minute – and they don’t get tired. With robotic labour, you can run a sorting and processing operation 24 hours, seven days of week, bringing long-term efficiency savings. One of the downsides – at the moment – is the cost. Sadako doesn’t yet have a commercial price for Wall-B, but Garnica estimates it would be in the region of €100,000. Meanwhile, the ZRR systems with two arms, for instance, come in at more than half a million euros, though Johansson explains: “The initial outlay would be recouped in the long run thanks to the low operating cost. Also, with the robotics, you can leave out a few steps in the process. As the robots are able to pick small and large objects at the same time, you don’t need to shred the waste at all. So you save in electricity costs.”

Both Sadako and ZenRobotics insist that over the long term, a robotic system would be cheaper than an equivalent human workforce. So, do Wall-B and his buddies represent the beginning of the end of human labour in the waste industry? Adam Read, a waste management consultant at Ricardo Energy & Environment, is unsure whether the future will be completely robotised. “It depends on whether MRFs are still the focal point of the waste system in 10 or 15 years. There may come a tipping point, when efficiencies of it and the assurances of the quality you’ll get with robotic labour, and the stars align around market prices and labour costs go up and the unit costs of robots come down, when that nexus starts to make a lot more sense.”

Read does envisage a definite use for robots in the coming circular economy, though: “I think the more we go circular and the more we can keep things separate so the issue of contamination and separation becomes reduced, I think robotic labour will make a great deal of sense. If you’re… moving stuff from one part of a site to another and you need to do that 24/7 and you need to be able to do stock checking at the same time... Well, a robot that scans a barcode, moves the material, updates the database and sorts the different types of metals would be a significant uplift.”

Of course, this could also affect the number of jobs that the circular economy will create (estimated by Green Alliance to be 200,000 in the UK alone if we follow the current development path and up to half a million if we extensively expand the circular economy). Read continues: “But then you’re reducing labour. I’m not sure where these people might go in the economic system at the moment. You could argue that it’s not a great living, that it’s not a great career, but nonetheless it’s providing income for families all over the UK. Robotisation may give you the odd efficiency, but it would have a massive impact.”

How big an impact remains the central question. Antonis Mavropoulos (also interviewed in the augmented reality feature – see page 34), the CEO of D-WASTE and chairman of the Scientific and Technical Committee of the International Solid Waste Association (ISWA), is convinced that some degree of robotisation is inevitable. “You have a lot of dirty work and physical work in difficult conditions, so in those situations I’d say robots would be very much preferred. When they become affordable, they will become mainstream in waste management. You won’t need hand separation by human workers. You won’t need a driver to compact the waste in the landfill any more. A robotic driverless compactor will do it very easily and this has been already tested.”

Adam Read, though, suggests that even this scenario may be some way off. “People are talking about robot collections, aren’t they? I’ve seen some dodgy videos that look like science fiction [like the one below, developed by the Volvo Group]. I mean, on a new housing estate where you’ve got uniform roads and wide paths and all those other things that make collections easy, yeah – why not? But along the higgledy-piggledy streets of London, along changing widths of grass verges and complicated back alley collections in the North West? I’m not so sure.

“You think of the way you see robotics in other sectors. They are either used for terribly repetitive and relatively simplistic solutions, or they are used for the complete extreme – in very hazardous environments or very dangerous situations where you don’t want to risk human life. Of course, there are always step changes. You hear the distant drums, but I’m not looking over my shoulder thinking, ‘No one is going to be wanting my advice in the next five years.’ We’re not going to have a brigade of robots on the street sorting our waste in the next decade. I just can’t see it.”

So does that mean we can stop worrying? Well, intriguingly, Antonis Mavropoulos suggests that rather than robots replacing humans the future might involve some sort of sci-fi-style interface between human and artificial intelligence. “Panasonic has recently carried out a very interesting experiment. Instead of having robots substitute workers carrying heavy loads, they have created robotic exoskeletons. The worker wears an exoskeleton and he can lift up to 40 or 50 pounds without any problem to his health, without being tired. Instead of lifting once every five minutes, he can lift once every two minutes. He is more productive, safer, he keeps his work and actually makes more money. I’d say the use of exoskeletons instead of robots is something we need to think carefully about.”

Now, that does sound like something from the pen of Philip K Dick or Isaac Asimov. Man and machine working in harmony to reduce waste? It certainly sounds preferable to some of the dystopian futures we’ve been used to reading...

Related Articles

As drone use takes off, it’s only a matter of time before they find their place in waste management. In fact, they can already be seen flying over landfills and cropland, monitoring waste, with more applications sure to follow.